As a naturally aspirated engine, the 5.7 HEMI is an excellent choice. It has a more aggressive camshaft, which, combined with the Hemi design, produces a significant increase in airflow. In our 5 best 5.7L V8 mods guide, we touched on cam upgrade kits briefly. We’ll be looking into cam enhancements in great detail now. In this essay, we’ll go through the many aspects of upgrading your 5.7 HEMI camshaft, from the advantages to the costs, from the lifters to the springs.
About 5.7 HEMI Camshaft Upgrades
When compared to other common performance upgrades, such as headers, intakes, and exhaust systems, camshafts are a lot more complicated. There are crucial topics including duration, valve lift, and lobe separation. With the 5.7 HEMI camshafts, there are additional variances in MDS vs non-MDS cams as well as VVT.
In the following paragraphs, we will go over all the fundamentals you need to know before purchasing a 5.7 HEMI camshaft kit. Then, we’ll discuss the advantages of cam kits and provide a short list of some great choices for the 5.7L V8.
MDS vs Non-MDS HEMI Cams
The MDS system is standard on all 345 HEMI engines manufactured in 2006 and after. Cars with a manual transmission as well as HD 2500 and 3500 trucks do not use MDS. There are certain variances with the cams, and you cannot change an MDS cam into a non-MDS HEMI. You may, however, utilize non-MDS cams in 5.7L V8’s with MDS granted you do the following:
- Adjustments made specifically to turn off MDS
- Use non-MDS lifters
- sMDS solenoid delete plugs (optional) (optional)
In truth, most aftermarket camshafts do require uninstalling the multi-displacement mechanism. If you own a 5.7 HEMI and want to get rid of MDS, you can get a whole kit from Texas Speed & Performance (TSP). All necessary gaskets, seals, and nuts, as well as the MDS delete plugs and non-MDS lifters, are included. You’ll still need adequate tuning to account for the change, but that’s important for cam upgrades anyhow.
Swapping in a 392 HEMI camshaft is one of a few cam alternatives that will maintain MDS. There are also a couple aftermarket cam improvements that are compatible with MDS. When looking for optimal efficiency and dependability, though, erasing the system is typically the best option.
5.7 HEMI Cam Upgrade Specs
It’s typical to see cams referred to with a series of numbers that appear pretty incomprehensible. For example, the TSP Stage 3 NA cam appears as: 223/232 .582/.582 113+3. All these figures don’t make any sense; can someone please explain them? It’s a really valid question, but worry not. Let’s look at all of the numbers and explain the meanings:
The duration of the valve at a lift of 0.050″ is equal to 223/232.
- 582/.582 = valve lift
- Lobe Separation Angle (LSA) = 113 + 3
- The factory-issued 5.7 VVT Eagle has auto-transmission specs of 186/208.499/.493 115.
5.7 HEMI Camshaft Valve Duration
The first figures reflect valve duration for the intake and exhaust valves, respectively. The usual unit of measurement for duration is 0.050′′ of valve lift. Anyway, this is the amount of time – measured in degrees of crank rotation – that the valve is open.
Valve duration is a measure of the total time that the intake and exhaust valves are open. More air and fuel can be pumped into the cylinder if the valves are left open for a longer period of time. This is especially critical at high-rpm where valves are opening and closing very quickly. Generally, longer duration is beneficial for top-end power while less length promotes low-end torque.
The typical upgrade for the camshaft in a 5.7 HEMI is a duration of 214 or 222 degrees. At about 226/235, you may expect more aggressive cams to arrive. When all other factors are held constant, a longer duration will result in greater peak power gains at the expense of smaller gains in low-end torque (or potentially even losses in torque).
5.7L V8 Valve Lift
In the next passage, we will discuss the 5.7 HEMI valve lift. The intake and exhaust lifts represent the distance the valve opens from its seat. More air enters and exits the cylinder as the 5.7L V8 HEMI valves are opened.
Power and torque are often increased all the way across the powerband with higher lift cams. As such, there isn’t a major tradeoff for horsepower or tq like there is with valve duration. However, there are a number of elements that should be considered when deciding how much of a lift to run.
To begin with, the valve springs must be upgraded when installing high-lift cams in a 5.7 HEMI engine. This is something we encourage on the HEMI regardless of lift, and we’ll circle back to this issue in a few moments. Too much elevation can cause problems apart from the potential requirement for further head work. Anything over 0.650″ of lift is usually only seen in the racing scene.
Many 5.7 HEMI camshafts include intake and exhaust valve lifts in the.580 to.600 range. Some exceptionally high-lift choices like the Comp Cams Stage 3 are as high as .632/.619.
Dodge 5.7 Cam Lobe Separation Angle
Complexity arises at the Lobe Separation Angle (or LSA for short). In the first scenario, the LSA is 113+3. For the time being, let’s disregard the +3 and focus on the 113. LSA is the number of degrees between the highest lift locations of the intake and exhaust lobes. This not only influences the powerband but it also plays a huge role in idle quality, vacuum, and cam rpm range.
To advance the cam timing by three degrees, or “+3,” the intake centerline must be moved forward (ICL). We need to stop here because we’re becoming too technical.
Anyway, higher LSA is ideal for a wider powerband and also increases top-end power. Though the low-speed torque provided by the 5.7 HEMI LSA is increased, the powerband is drastically reduced. Last but not least, a reasonable range for LSA on 5.7L V8 cams is 112-116. We recommend consulting an experienced shop or conducting much more study if you need to deviate significantly from that.
Other 5.7 HEMI Cam Considerations
There is still more to learn about 5.7 HEMI camshaft upgrades. For this and other reasons, it’s best to consult a professional HEMI store or do extensive reading before making any cam kit purchases. You shouldn’t use this update if you want to learn the ropes as you go. Anyway, let’s go into a few more 345 HEMI cam subjects before selecting some of the best cams on the market.
Dodge 5.7L V8 Valve Spring Upgrades
We briefly discussed 5.7 HEMI valve spring upgrades before when we were discussing valve lift. The valve springs get more strain as the lift rises. As such, valve springs are a useful item to consider with high lift cams – especially cams pushing above 0.550 lift. That lift is typically exceeded by aftermarket camshafts.
When upgrading valve springs, it’s important to specify how much lift is allowed. Additionally, cam kits should include valve spring improvements or the ability to upgrade to appropriate springs. Kits from both Comp Cams and Texas Speed, for instance, include the appropriate valve springs for the cam profile.
5.7 HEMI Phaser Limiter or Lock Kits
The clearance between the pistons and the valves is an issue that hasn’t been discussed. In the 5.7 HEMI engine, the paths taken by the pistons and the valves cross each other somewhat due to the interference design. That can present complications when adjusting the valve lift and duration. Pistons and valves can injure each other if they come into touch.
Cam phasers in the engine allow for instantaneous camshaft positioning changes. It helps save gas and provides more torque. Excellent work all around. However, the phasers have such a vast range of movement that bigger, aggressive cams can cause the pistons and valves to collide.
Bring in the 345 HEMI phaser lock and limiting kits. With a limiter, such as this one from Comp Cams, the maximum amount of cam phasing that may be used is 14 crank degrees, 7 cam degrees. There are also lock kits that, as the name suggests, totally stop the cam phasers from making any movement. Limiter kits are often the best solution since some cam phaser movement does aid maximize power.
This is not a problem with non-VVT HEMI engines, as cam phasers are only used in newer models (2009 and beyond).
Complete Camshaft Upgrade Kits
Finally, there are several more components that may need replacement at the same time as the cam install. Many shops have multiple cam options. One alternative is simply getting a 5.7 HEMI camshaft without any other components. If you’re after the bare minimum with a mild cam, all you’d need is an MDS delete kit in conjunction with non-MDS lifters. Again, more aggressive cams will require additional parts like valve springs and phaser limiter/lock kits.
However, we highly advocate doing things right and going for a complete 5.7 HEMI camshaft assembly – especially on older HEMI’s. The cam, lifters, phaser limiter, pushrods, valve springs, spring seats, valve seals, and more are all included in the Comp Cams Master Cam Kit. It’s a fantastic time to replace or update all of these components while you set up your cam.
Change out the head gasket, valve cover gasket, and any other cheap but easily broken components. These additions shouldn’t increase labor costs and will make for a more stable system in the long run.
Full kits aren’t always necessary because cams are a pricey and difficult modification in the first place. If you’re going to put in the effort and expense, you might as well get it properly. It may be OK to cut corners, save money, etc. on modest upgrades. 5.7 HEMI cameras aren’t that, though. The total cost of installing cams by a professional mechanic can be $2,500 to $4,000. It’s not something you want to do the incorrect way and have to go back and do it all over again. Get it done properly the first time.
Benefits of 345 HEMI Cam Mods
Upgrading the camshaft on a 5.7 HEMI can have several positive effects.
- The range of 30-70+ hp
- Turns of a wrench 10-30+ lbf-ft
- Enhancing the Sound Quality of Power Bands
All the 5.7 HEMI camshaft upgrade benefits focus around performance. Aggressive cams optimized for top-end power can exhibit improvements of 70+ peak horsepower. However, if the camshaft is too large, the vehicle’s low-end performance may suffer, reducing its usability for daily driving.
Luckily, with the correct HEMI cams, you can boost your peak output and flatten your power curve. It’s not implausible to pick up 30-50whp up top while also seeing benefits on the low-end and mid-range. These camshaft choices provide an ideal power-to-weight ratio and broad powerband for everyday street driving.
Cams also give some fantastic sounds. Hearing a cammed 5.7 HEMI in action is an experience few people will ever forget. Cams are pricey so we wouldn’t recommend cams for sound alone, but it’s a wonderful extra advantage on top of the performance gains.
5.7 HEMI Cam Upgrade Summary
The HEMI design makes the 5.7L HEMI a powerful performance engine that can take in a lot of air. The 5.7L V8 can benefit greatly from a more aggressive camshaft, which will allow it to produce more power and torque. Cams are a powerful addition, but you need familiarize yourself with the fundamentals first (or work with a knowledgeable shop).
Several factors should be taken into account before settling on a camshaft.
Molecular Dynamics Simulation vs. Non-MDS Simulation (& delete kits)
- Technical parameters/profile of the cam
- Changes to the valve springs
- Kits with phaser limits and locks
- There are still other components that need to be updated or replaced.
5.7 HEMI camshaft upgrades can appear complicated at first, but with a little research, you’ll have it all figured out in no time. The preceding essay, at least in its main points, should serve as a solid foundation from which to launch a cam upgrade.
It’s safe to say that when it comes to 5.7 HEMI cam kits, Texas Speed and Comp Cams are your best bets. There are a variety of aims and needs that can be met with either of these high-quality, superb kits. If you’re looking for aggressive cams that yet have decent low-end and top-end performance, then the Comp Cams stage 2 or TSP stage 3 are excellent choices. Larger camshafts are often reserved for racing purposes, where they won’t be subjected to the rigors of daily driving.
